Electric arc lamp



Oct. 13, 1931. "r. c. RUSSELL ELECTRIC ARC LAMP Filed Feb. 11, 1928 2 Sheets-Sheet l Oct.

1931- T. c. RUSSELL 1,827,374

ELECTRIC ARC LAMP Filed Feb. 11, 1928 2 Sheets-Sheet 2 7/9/ /&' 7232a Patented Oct. 13, 1931 PATENT OFFICE THOMAS C. RUSSELL, OF CmCAGO, ILLINOIS,

ASSIGI'TOIB' 'IO ULTRA VIOLET GENERATOR CORPORATION, OF CHICAGO, ILLINOIS, A GOBLORA'IION OF ILLINOIS mnc'rarc aac Lam? Application filed February 11, 1828. Serial No. 263,548.

My invention relates to electric arc lamps in which are used specially pre are'd electrodes containing rare minera s or producing an arc whose light is rich in healing and I, health iving and restoring rays, such as the by the unit, so as'to ultra vlolet ray, and the eneral object is to produce a more practical amp which can be adjusted and operated with greater precision and efficiency.

More s ecifically, one important object is to provi e a simple, compact unitary electrode supportin structure and a simple housing and re ector structure into which the electrode supporting unit may be readily inserted and accurately secured.

Another important object is to provide improved arrangement for adjusting the electrodes for starting the arc and for operation, and for positively holding the electrodes in properly spaced operating relation so illlgi; a steady and efiicient arc is maintaine Another important object is to provide electrode supports which will accurately support the electrodes but will be sufficientl resilient, particularly when the arc is starte to prevent displacement or breaking of the electrodes.

[another important object is to provide improved fuse arrangement for opening the circuit when the electrodes have been consumed to a predetermined extent.

Another important object is to provide for isolating and carrying ofi the heat generated protect the operator and user and prevent overheating of the electrode supports and electrical terminals.

The above and other features of my invention are incorporated in the structure shown on the drawings, in which Fig. 1 is a side elevation of the lamp with the housing and reflector in vertical section,

Fig. 2 is a section on plane 22 Fig. 1,

Fig. 3 is a section on lane 3-3 Fig. 1,

Fig. 4 is a section on p ane 4-4 Fig. 3, and

Fig. 5 is a side elevation showing a modified arrangement.

The electrode supporting structure comprises a base of porcelain or other electrical insulating and heat refractory mateelectrode may rial, the base having the hollow flaring upward extension 11 provided with external g)rooves 12 for receiving resistance wire 13.

n diametrically opposite sides the base has the transverse depressions or grooves 14 and 15, the groove 14 seating the bar 16 and leaf spring 17 18. The har 16 an spring 17 are secured by the screw 19 which extends into the vertical channel 20 in the base. 10 and threads into the terminal blade 21 which extends through the passage 22 and projects a distance below the base. The bar 18 is secured by the screw 23 which extends into the vertical channel 24 and threads into the terminal blade 25 extending through passage 26 and projecting a distance below the base parallel with the blade 21. The projecting ends of the blades are adapted to receive the connecting socket (not shown) of a current supply circuit in the well known manner. The screw 19 electrically connects the spring 17 with the terminal blade 21 but the bar 18 is insulated from the terminal blade'25 by the base material and the insulating washer 27 head of the screw 23.

Secured to the spring 17 opposite the outer end of the bar 16- is the jaw member or frame 28 which extends parallel to'the spring and has in its outer side the longitudinal seating groove or though 29 for the electrode 30. Opposite this trough the end' 31 of spring 17 is ofi'set a distance to form a yieldin jaw member for cooperating with the jaw rame 28 toform a receiving socket for the electrode and to firmly but yieldingly clamp the electrode in place. The end 31 is preferably curved or flared as shown so that the under the socket.

The bar 18, at its outer end, terminates in the grooved jaw 32, and secured to thebar is the spring clamp 33 which cooperates with the jaw to form a socket for receiving the electrode 34.

The electrode supporting spring 17 is flexible to permit adjustment of the electrode relative to the electrode 34 for starting and regulating the arc. The bar 18, however, is comparatively stiff but be readily inserted into the will yield sufiicientand the (groove 15 seating the bar 1y to give should undue pressure be exerted against the electrode 34 when the are 13 started. The spring clam 33 will also yield and prevent breakage of t e electrode.

Describing now the adjusting arrangement for the electrode 30, the aw member 28 is secured to the spring 17 by the screw 35 and nut 36, the screw extendin toward the bar 16 and receiving the threa ed neck 37 of the ferrule 38 at the end of the adjusting lever or handle 39. The neck engages in the longitudinal slot 40 at the end of the bar 16, and inside of the bar the neck-has the collar 41. The spring 17 is tensed so that it will always tend to swlng toward the bar 16 and hold the electrodes apart. Such swing is resisted by the abutment of the collar against the bar. However, when the lever 39 is axially rotated in counter clockwise direction the screw will be shifted along the lever neck and the spring will be swung to move the electrode 30 toward the electrode 34 and the arc can thus be readily adjusted. When the arc is to be started the lever is swung laterally (to the right in Fig. 1) and the spring is then directly flexed and the end 'of electrode 30 engaged with the end of electrode 34, and then upon gradual separation of the electrodes the arc will be started. The lever is then rotated axially, as explained, to adjust the arc gap with accuracy and precision. The electrode 30 can thus be positively adjusted and the spring structure 17 will firmly hold the electrode in adjusted position while the lamp is in operation. At the same time there will be sufficient yield to prevent breaking of the electrode should it be accidentally subjected to undue lateral pressure or strain. As shown, the electrodes are preferably supported and adjusted so that the gap between them gradually increases toward their supported ends. This arrangement will prevent creeping of the arc and will keep it localized between the outer ends of the electrodes.

To safeguard the apparatus, fuse structure is provided for opening the circuit when the electrodes have been consumed to a predetermined extent. The bar 18 supports a shelf 42 which extends horizontally above the bar and the spring 17 behind the electrode supporting socket structures. Sheet metal arms 43 and 44 extend from this shelf and terminate above and outside of the socket structures. The ends of the arms have spring pressure clips 45 and 46 secured thereto to form spring jaws for receiving the ends of a fuse band or wire 47 which extends above and across the electrodes in front of the supporting sockets to be fused by the heat of the arc and to open the circuit before the arc comes close enough to the electrode supporting structure to cause overheating thereof.

The arm 43 is secured to the shelf 42 to be in electrical engagement therewith, but the screw 48 which secures the arm 44 to the shelf is insulated from the shelf by the insulation 49. This screw forms one terminal for the resistance winding 13. The blade 25 which extends u wardly in the hollow base extension 11 orms the other terminal for the resistance.

The circuit for the structure in Figs. 1 to 4 is as follows. As before stated a supply circuit socket is applied to the projecting ends of the terminal blades. Current then flows from the blade 21 through the spring 17 and bar 16 to the electrode 30, then through the arc and the electrode 34, bar 18, shelf 42, arm 43, fuse 47, arm 44, the resistance winding 13 and back to the supply circuit through terminal blade 25.

The unitary electrode structure is detachably supported on the horizontal shelf 50 extending from the bracket 51 to which the reflector 52 is secured. The lower end of the unit base extends into the opening 53 in the shelf and the flange 54 on the base seats on the step 55 surrounding the openin Clips 56 attached by screws 57 to the shel bear on the tro es and part of their supporting sockets, and also the fuse, extend into the reflector through an opening 58.

A cylindrical hood or housing 59 of sheet metal is detachably secured to the shelf and reflector by screws 60 and 61. At its top the housing has the heat outlet 62 above which is supported the cap plate 63 by a bracket 63'. I preferably also surround the resistance sup porting extension 11 by a chimney 64 through which cool air entering at the bottom of the housing may flow close to and past the hot resistance wire to carry the heat out through the outlet 62. This chimney prevents the heat from spreading to the reflector, and an additional baflie plate 65 may be interposed between the chimney and reflector and, as shown, may be secured to the chimney. Air will also travel through the housing outside of the chimney and assist in keeping the supporting unit cool.

A batfle 66 may be located on the extension 11 below the resistance to ward off the heat from the electrode supporting structure. As shown in Fig. 1 this baflle may be a metal plate held in place by the grooves 12, or, as shown inFigs. 2 and 4 the baflie may be in the form of an annular flange 67 integral with the resistance supporting frame. The diameter of the baflie is sufliciently less than that of the chimney so it will not interfere with flow of air through the chimney.

The bracket 51 on which the reflector is mounted has the supporting arm 68 adjustably connected by a joint 69 to a post 70 which telescopes in a pedestal tube 71 terminating in a base (not shown). By means of a set flarzlge and hold the unit in place. The elecscrew 7 2 the arm 68 is locked in adjusted posisea-1,314

p the electrode supporting structure. The refiector 74 has a housing 75 secured thereto and supported on the rear wall of the hous-v ing are the upper and lower brackets 76 and 77. A comparatively rigid bar 78. extends forwardly from the upper bracket while from the lower bracket extends the spring bar 79. The bars extend into the refiector through opening 80 and terminate in jaw structures 81 and 82 for supporting the electrodes 83 and 84. Spring clips 85 and 86 are secured by screws 87 and 88 to the structures 81 and 82 for resiliently clamping the electrodes in place. The bars 78 and 79 are insulated from their sup orting brackets by insulation 89 and 90 antfcurfent supply conductors 91 and 92 connects with the screws and thus with the electrodes. The resistance 93 may be included in the circuit at a point remote from the lamp so that the lamp will be entirely free from the heat generated by the resistance. The conductors pass out of the housing through the opening 94.

For adjusting the spring supported electrode 84, a rod 95 threads through an insulating bushing 96 supported by the spring bar 79 and extends through a slot 97 in the lower wall of the housing and has the grip 98. A collar 99 on the rod abuts against the innerside of the housing wall. The spring bar 79 tends to swing to move the electrode 84 away from the electrode 83 but is resisted by the abutment collar. By axially rotating the rod its threaded engagement in the bushing 96 will force the spring bar inwardly or permit it to relax and thus accurate adjustment can be made for an efiicient arc. To start the arc the rod is swung laterally to bring the electrode 84 in contact with the electrode 83.

I thus provide a simple, inexpensive and eflicient lamp comprising a compact unitary electrode supporting structure which is readily accessible and detachable and therefore easily kept in proper working condition and which can be readily and conveniently connected with a current supply circuit.

I do not desire to be limited to the exact structure and arrangement shown'as modifications and changes are possible which'will come within the scope of my invention.

I claim:

1. An electrode supporting structure comprising a base of insulating material, means on said base for connecting to an electric cirsuit, a resilient bar, an electrode receiving socket connected with said base by said resilient bar, a comparatively rigid bar, an electrode receiving socket connected with said. base by adjacent to said resilient bar having a slot, a lever extending through said slot and having a threaded bore, a screw extending from said resilient bar and threaded into said bore,

said comparatively rigid bar, a plate and an abutment collar on said lever engaging said plate, said resilient bar tending to swing away from said rigid bar, rotation of said lever relative to said screw causin swing of said resilient bar toward the rigi bar or permittin relaxing thereof to swing away from sai rigid bar.

2. An electrode supporting structure comprising a base, a spring bar extending from,

said base and terminating in an-electrode'receiving socket, a less resilient bar extending from said base and terminating in an electrode receiving socket, a plate alongside of said spring bar, a threaded stud on said spring bar, and a lever abutting against said plate and receiving said stud whereby axial rotation of said lever will positively swin said s ring bar or permit relaxation thereo for ac justment of said bars and electrodes supported thereby, bodily swing of said lever causing swing of said spring bar independently of the threaded engagement of said lever and stud.

3. An electrode supporting structure comand terminating in an electrode holder, and

a lever having screw threaded engagement with said spring bar and having a shoulder abutting against said frame, said threaded engagement and said shoulder abutment cooperating upon axial rotation of said lever to 7 swing said spring bar or to ermit relaxation thereof to thereby effect a justment of said electrode holders and electrodes held thereby, swing of said lever directly swinging said spring bar and electrode supported thereby.

4. In an electric arc lamp the combination with a bracket, a reflector mounted thereon, and a shelf on said bracket having an opening, of a unitary electrode supporting structure comprising a base adapted to seat in said shelf opening and having terminal blades extending below said opening for connection with a current supply circuit, electrode supporting arms extending from said base and terminating in sockets for receiving and supporting electrodes within said reflector, a resistance on said base above said arms, a chimney surrounding said resistance, and a housing enclosing said unitary supporting structure and having an outlet for the escape of above said arms, a chimney surrounding said resistance, a bafile wall between said res stance and said arms, and a housing enclosing said electrode supportin structure, sm 5 housing having an outlet a jacentto the chimney outlet. 7

6. In an electric arc machine, the combination with a supporting bracket having an opening, of a unitary electrode supporting 10 structure comprising a base seated on sai bracket and having a vertical extension, electrode supporting arms extendin from said base and terminating in electro e receiving sockets adjacent to said reflector opening, ii a resistance wound on said extension, electrical connecting means on said base, a housing enclosing sa1d base, there being air space between said base and housing walls for the upward flow of air and said housing having a top outlet for such air, and a chimney surrounding said resistance for localizing part of the air flow close to the resistance to carry 01f the heat therefrom.

7. In an electrical arc machine, the combination of a reflector having an opening, a

housing extending from said reflector, a supporting structure within said. housing, a spring arm extending from said supporting structure and terminating in an electrode receiving socket at said reflector opening, a comparatively rigid arm extending from said supporting structure and terminating in an electrode receiving socket at said reflector opening, and a lever having threaded connection with said spring arm and means holding said lever against lon 'tudinal movement whereb axial rotation 0 said lever will positively ex said spring arm or permit relaxation thereof to thereby cause relative adjust- 40 ment of said sockets and electrodes held thereby, said lever being free for lateral swing to cause flexure of said spring arm independently of said threaded connection.

In witness whereof, I hereunto subscribe my name this 30th day of January, 1928.

THOMAS C. RUSSELL. 

